Emulsion polymerization process employing an oxazoline as chain transfer agent

ABSTRACT

An improved process for emulsion polymerization by using as the initiator and the surfactant an oxazoline corresponding to the formula:   where R is an alkyl group of 1-19 carbons, and R1 and R2 are methyl, ethyl, hydroxymethyl, or the group RCOOCH2-.

United States Patent [191 J urisch Dec. 30, 1975 EMULSION POLYMERIZATIONPROCESS EMPLOYING AN OXAZOLINE As CHAIN TRANSFER AGENT [75] Inventor:

[73] Assignee: Commercial Solvents Corporation,

Terre Haute, Ind.

[22] Filed: Oct. 15, 1973 [21] Appl. No.: 406,760

Louis A. Jurisch, Marengo, Ill.

[56] References Cited UNITED STATES PATENTS 11/1963 Delacretaz 260/935 W11/1969 Streck et al 260/935 R 3,678,065 7/1972 Frump 260/307 3,687,8888/1972 Frump et al. 260/807 3,692,757 9/1972 Dowbenko 260/307 F OTHERPUBLICATIONS Kirk-Othmer, Encyclopedia of Chemical Technology,

2nd Edition, Vol. 14, lnterscience Pub., New York, pp. 756, 757.

Primary ExaminerPaul R. Michl Attorney, Agent, or FirmRobert H. Dewey;Howard E. Post 57 ABSTRACT An improved process for emulsionpolymerization by using as the initiator and the surfactant an oxazolinecorresponding to the formula:

where R is an alkyl group of 1-19 carbons, and R and R are methyl,ethyl, hydroxymethyl, or the group RCOOCH 11 Claims, N0 DrawingsEMULSION POLYMERIZATION PROCESS EMPLOYING AN OXAZOLINE AS CHAIN TRANSFERAGENTv BACKGROUND OETHE INV TIQN SUMMARY OF THE INVENTION It is anobject'of this' invention to provide an im proved process for theproductionof polymers.-

It is another object of this invention to provide an improved processfor the production of polyrnersby conducting the polymerization in thepresence of a chain transfer agent.

It is a third object of this invention to provide an improved processfor the production of novel polymers.

Other objects will be apparent to those skilled in the art from thedisclosure herein.

It is the discovery of the present invention to provide an improvedprocess for the production of polymers and copolymers by emulsion orsolution polymerization by effecting said polymerization in the presenceof an oxazoline chain transfer agent corresponding to the formula:

wherein R is an alkyl group of 1-19 carbon atoms and R and R arehydrogen, methyl, ethyl, hydroxymethyl or the group RCOOCH. R and R canbe the same or different.

DETAILED DISCUSSION In the practice of the present invention, anoxazoline corresponding to the above formula is incorporated in thepolymerization mixture in an amount of about 0.1% to about based on theweight of the monomers. Generally about 10-15% is preferred. No otherchain transfer agent is employed, but various other additives known inthe art, such as initiators, can be used as desired.

The use of an oxazoline as the chain transfer agent has the advantage ofeliminating disagreeable odors in the work room.

In one embodiment of the present invention, polystyrene prepared in thepresence of an oxazoline wherein at least one of R or R is hydroxymethylis further reactable, e.g. with hexamethoxymethylmelamine or tion areknown in the art, and many of them are corn mercially available. Theusual commercial materials are satisfactory. These oxazolines can alsobe prepared by the method of Purcell, U.S. Pat. No. 3,336,145, which isincorporated herein by reference thereto.

The invention will be better understood with refer-i.

ence to the'following examples. It is understood, however, thatytheexamples are intended for illustration only and itis not intended thatthe invention be limited thereby.

EXAMPLE 1 A mixture of oxazolines was prepared by reacting pelargonicacid with tris(hydroxymethyl)amino? methane in a 1.5:1 mole ratio. A 50g portion of the mixturewas dispersed in 500 g distilled watercontaining 10 g hydroxyethyl cellulose. This mixture was heated toreflux for 15 minutes, then allowed to cool to 180F. There was graduallyadded in about an hour with stirring 350 g of styrene and simultaneously2 g ammonium persulfate dissolved in 20 g distilled water. Heating at180F was continued for another 30 minutes and it was then allowed tocool. A stable, white latex was obtained.

A sample of the latex was laid down on a smooth substrate and dried atroom temperature. A rough film was obtained. When baked at 400F for 5minutes, a clear, very hard but reasonably flexible film was obtained.

A sample of the latex was mixed with hexamethoxymethyl melamine, laiddown on a smooth substrate and baked at 400F for 10 minutes. Anultra-hard opaque film was formed. It was immersed in water for an hourat room temperature and barely softened. Another sample of the bakedfilm was heated at 400F for 4 hours. No discloration occurred and itretained a hardness of 6H on aluminum and passed a one-eighth inchmandrel bend. When tested for solvent resistance, it passed rubs withmethyl ethyl ketone.

EXAMPLE 2 The foregoing experiment was repeated in all essential detailsexcept that methylated melamine (Resimene X-74O manufactured by MonsantoChemical Company was used) was substituted for hexamethoxymethylmelamine. Similar results were obtained.

EXAMPLE 3 The experiment of Example 1 was repeated in all essentialdetails except that vinyl acetate monomer was substituted for styrene ata temperature of F. During the mixing the temperature rose to where itwas maintained for 30 minutes. A sample laid down on a substrate, driedtack-free in 3 minutes.

EXAMPLE 4 A mixture of oxazolines was prepared by reacting isononanoicacid, 1.5 moles with tris(hydroxymethyl- )amino-methane, 1 mole.

A 75 g portion of this oxazoline was dispersed in a mixture of styrene500 g, methacrylic acid 75 g, and 70% benzoyl peroxide 20 g. Thissolution was added dropwise with stirring over a period of 1 hour to 300g of 2-butoxy-l -ethanol at a temperature of 340F. Heating was continued1 hour, then the solution was cooled to 175C. To this mixture was added95% 2-amino-2- methyl-l-propanol 100 g to neutralize the acid. Themixture was then allowed to cool to room temperature. The product wasclear, semi-solid having a viscosity of about Z, Gardner; a color,Gardner of l and nonvolatile content of 70%.

To the product obtained above was added hexamethoxymethyl hexamethylenetriamine 30% to give a white, water-reducible dispersion.

A sample was drawn down on a smooth substrate and baked at 400F forminutes; there was obtained a clear, hard film with high gloss, freefrom discoloration and possessed good flexibility.

I claim:

1. In a process for the production of the homopolymers of styrene and ofvinyl acetate, or the copolymer of styrene and methacrylic acid byemulsion polymerization or by solution polymerization, the improvementconsisting of using as the chain transfer agent an oxazolinecorresponding to the formula:

where R and R are hydroxymethyl, or the group RCOOCH and R is an alkylgroup of l to 19 carbon atoms.

2. The process of claim 1 wherein said oxazoline is present in an amountof about 0.1 to about 20% based on the weight of the monomers.

3. The process of claim 1 wherein said oxazoline is present in an amountof about l0-l5% based on the weight of the monomers.

4. The process of claim I wherein R and R are hydroxymethyl.

5. The process of claim 1 wherein R and R are the groups RCOOCH 6. Theprocess of claim 1 wherein the polymer to be produced is polystyrene.

7. The process of claim I wherein the polymer to be produced ispolyvinyl acetate.

8. The process of claim 1 wherein the polymer to be produced is thecopolymer of styrene and methacrylic acid.

9. The process of claim 1 wherein said homopolymer is polystyrene.

10. The process of claim I wherein said homopolymer is polyvinylacetate.

11. The process of claim I wherein the copolymer of styrene andmethacrylic acid is produced.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No.3,929,743 DatedDecember 30, 1975 Inventor(s) LOuls J'uI'lSCh It iscertified that error appears in the above-identified patent and thatsaid Letters Patent are hereby corrected as shown below:

In the Abstract, the formula H c-- c; R should read H2C---C R I $1 I o N)1 C I L R Column 1, line 50, "RCOOCH." should read RCOOCH2- Signed andScaled this Seventeenth Day of Ma 1977 [SEAL] Arrest:

RUTH C. MASON C. MARSHALL DANN Arresting Officer Commissioner oflaremsand Trademarks

1. IN A PROCESS FOR THE PRODUCTION OF THE HOMOPOLYMERS OF STYRENE AND OFVINYL ACETATE, OR THE COPOLYMER OF STYRENE AND METHACRYLIC ACID BYEMULSION POLYMERIZATION OR BY SOLUTION POLYMERIZATION, THE IMPROVEMENTCONSISTING OF USING AS THE CHAIN TRANSFER AGENT AN OXAZOLINECORRESPONDING TO THE FORMULA:
 2. The process of claim 1 wherein saidoxazoline is present in an amount of about 0.1 to about 20% based on theweight of the monomers.
 3. The process of claim 1 wherein said oxazolineis present in an amount of about 10-15% based on the weight of themonomers.
 4. The process of claim 1 wherein R1 and R2 are hydroxymethyl.5. The process of claim 1 wherein R1 and R2 are the groups RCOOCH2-. 6.The process of claim 1 wherein the polymer to be produced ispolystyrene.
 7. The process of claim 1 wherein the polymer to beproduced is polyvinyl acetate.
 8. The process of claim 1 wherein thepolymer to be produced is the copolymer of styrene and methacrylic acid.9. The process of claim 1 wherein said homopolymer is polystyrene. 10.The process of claim 1 wherein said homopolymer is polyvinyl acetate.11. The process of claim 1 wherein the copolymer of styrene andmethacrylic acid is produced.